Treatment of calcium magnesium chloride



, July 19, 1938.1 P. R. MARTIN TREATMENT 4o F CALCIUM MAGNESIUM QHLQRIDE 'Filed Dec. s, A1934 f Pez@ Hmmm;

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Patented July 19, 1938 UNITED .STATES PATENT ori-ICE i :I TBEATBIENT MAGNESIUM y Peter R. Martin, Chicago, Ill., assignor to Fuel Treating Products Co., Chicago, Ill.

Application December 3, 19,34, Serial No. 755,746

3 Claims.

My invention relates to the treatment of materials, particularly to the treatment of calcium magnesium chloride and similar materials, to recover them in a substantially dry solid pulveru- 5 lent form;

According to some methods for obtaining sodium chloride when deposits thereof are found underground, the salt is dissolved in water and the brine pumped to the upper surface and processed for the removal of sodium chloride therefrom. Other valuable pro-ducts are also obtained, such as bromine andv the final substance subsequent to the evaporation of most of the water therefrom consists principally of so-called calcium magnesium chloride which is in itself a l'mixture of various combinations of the three elements mentioned and, at elevated temperatures is a rather thick, pasty mass. In recent yearsit was found that this material has valuable properties, resulting principally from its hygroscopicity; for example, -it is spread over freshly laid concrete and by attracting moisture from the air increases the'setting time of the cement with the result "that an improved concrete product is produced.

The recovery of the calcium magnesium chloride in a suitable condition for shipping has been 4a considerable problem. According to the method heretofore employed, the dark looking residue was heated for a considerable time to about 350 F. to drive off water. v,This liquid was then poured into drums, allowed to cool for 24 hours or longer and more hot liquid added to' take care of shrinkage during the cooling. The product was then left to stand as long as several weeks, depending upon the nature ofthe weather, before it was s uiciently solid for use. The drum was then broken away from around the solid salt body and the solid salt body broken up by hand labor, using sledges. etc. The relatively large pieces formed by hand labor were then ground and thefiinal product was a mixture of pulverulent material and lumps ranging from V4" to 2" in diameter. The process used heretofore was expensive, required a great deal of time and was generally objectionable, but no other suitable means for processingthe material was found in spite of considerable investigation.

The principal object of my invention is the provision of an improved means and method for treating calcium magnesium chlorideand .similar hygroscopic materials. Another object is the provision of a method of and means for treating the material .continuously to reduce it to solid 55 pulverulent form. Other objects and features of the invention w1l'l`be.,apparent as the detailed description progresses.

In general, I accomplish the object of my in- I I' vention by spreading the material onto 'a relatively thinmetal plate which is preferably in 5 the form of a belt of sheet steel, chill the platel by suitable means,. forI example spraying the underside of the plate with cool or cold water, and cause the material to be broken off of the plate in the form of chips or flakes which are 10 in themselves of a suitable size but which are readily broken into smaller fragments by suitable comminuting apparatus.

One embodiment of the mechanism for carrying out this process is shown in the accompany- 15 ing drawing, wherein- Fig. 1 is a fragmentary elevational view, partly in section, showing the preferred form of the :C apparatus;

Fig. 2 is an end view looking at the discharger20 a..

end of the apparatus, part of the apparatus be-,l ing removed and the metal beltshown in section to indicate the relationship of the parts;

Fig. 3 is an -enlargeozl fragmentary sectional view taken on the line 3 3 of Fig. 1; and 25 Fig. 4 is a fragmentary elevational view, partly in section, showing a'modied feeding means.

` Referring now to the drawing, the mechanism shown comprises a frame I0 of suitable shape to support the operating parts of the mechanism 301 on which is rotatably carried a pair of pulleys II and I2 around which travels an endless rustl' resisting steel belt I3. The pulley II is journalled in fixed bearings carried by an extension of the frame I0 while the pulley I2 has a center 35 shaft journalled in apair of blocks I4 (one is shown in Fig. 1) shaped like a cross head and slidable between a pair of rails I6, supported by i a pair ofV angles I1, secured to a frame extension. Springs I8 move the blocks I 4 in a direc- 40 tion to apply tension to the belt and adjusting screws I9 are provided for limiting the tension on the belt or for decreasing the tension suiilciently to make possible an easy removal or adjustment of the belt. 45

The pulley I2 is an idler, the drive being entirely through pulley I I at the delivery. end of the apparatus. A sprocket gear 2| is secured to turn with the pulley I I by either being secured 1 to the pulley shaft or secured to the end thereof. 50 A driving sprocket gear 22 is provided, a sprocket chain 23 serving to transmit motion of the drlving sprockety 22 to the sprocket 2I. A motor 24 (Fig. 2) carried on a separate frame, suitably supported as. for example, on the oor, driis gears between the motor shaft and the shaft 26,

as indicated generally in the drawing. I may,

however, -employ a` large relatively low speed motor with suitable results.

The belt is supported by suitable means intermediate its length. In the drawing I show a plurality of rollers 21 carried on shafts 28 journalld in bearings 29, carried on the frame by .means of angles or other suitable frame extensions. These rollers are employed at top and bottom, the roller shafts being shown only in Fig. 3 and identified by the reference character 28.

The calcium magnesium chloride or other material treated is delivered through a hopper 3|.4

In the preferred embodiment I show the hopper equipped with. a pair of rollers 32 adjustable with respect to each other so as to provide a feeding space therebetween and of approximately the same width as the belt I3. By adjusting the rollers, a layer of the material to be treated of substantially the exact thickness desired can be applied continuously to the belt asv it moves in the direction indicated by the arrows. It will be noted that although theribbon of material passes almost directly downwardly, the movement of the belt causes the material to spread out uniformly in the direction which the belt takes.

The belt is cooled byvapplying cooling means to the bottom surface of the upper reach thereof. A suitable and very satisfactory cooling means is water. For the utilization of water' at proper temperature I provide a pipe system 33 equipped with a number of sprinkler heads 34 so arranged as to cause the water to strike substantially the entire lower area of the belt. The water is delivered to the pipe system under sufficient pressure to produce a proper spray action. The pressure may be regulated by means well known in the art to deliver a sucient amount of water to cause a proper cooling action. If the water is relatively warm, more of it may be required; while relatively cold water need not be supplied inthe same quantities to produce the same result. I have found that water having a temperature of as high as 80 or 85 F. can be used with fair results although water somewhat colder is preferred. Since the'apparatus is designed so that extremely cold water is not necessary, the apparatus can be supplied usually by pumping 'water from natural sources, such as rivers, even during the latter part of the summer when the temperature thereof is relatively high. I have found that well water-can be used tovery great advantage because its temperature will be uniform within a few degrees during the entire year and less adjustment is required to be made from season to season.

By the use of an adjustable feeding means, the thickness of the layer of material applied to the belt can be regulated. This is another adjustment which can be made to allow for difference in weather conditions and the temperature of the cooling water employed. In general, the thickness of the material should be between approximately 1,32 of an inch and 1/4 of an inch. I make the layer thin enough sothat the materialwill solidify before it reaches the end of its' travel path on the belt but at the same time as thick as possible consistent with proper performance in'order to increase the capacityof the machine.

The material is in'the form of a substantially solid sheet by the time it reaches the pulley Il.

The angular travel of the belt at this point has the effect of partly breaking up the material and causing it to fall by its own weight around the periphery of the pulley H and be discharged into or onto suitable handling apparatus, for example, a conveyor 36, indicated schematically in Fig. l. As a precaution, however, and to .positively remove such material as may adhere to the belt, I provide a take-off scraper 31. The material delivered to the conveyor 36 is in the form of thin chips suitable for use for most purposes, but` capable of being readily broken up further if necessary. I have found that if the material has been decreased in temperature to approximately 85 F. it will solidify sufficiently.

In order to prevent the cooling water from reaching the top of the belt, I provide two strips of felt 38 or other sealing material between the frame and the belt. To support the felt in the embodiment shown, I use the same angular portion of the frame which supports the bearings for the rollers 21. I may, however, provide any other suitable seal at the edges of the belt for preventing the cooling liquid from reaching the top of the belt.

The pipe system is verted truncated cone. This housing 39 is closed at the top by the belt itself and the frame to which it is secured. It is open at the bottom, however, so as to direct the water downwardly to the lower section of the belt after it has fallen by gravity following its contact with the upper portion of the belt. Below the lowermost portion of the belt I provide a continuous trough 4l with a drain 42 for continuously removing water after it has run off the lower section of the belt. This not only helps to keep the belt clean but it also cools'it somewhat and conditions it for the reapplication of the material being treated after this lowerv portion of the belt reaches the hopper 3|.

In the further conditioning of the belt I provide a spring-pressed cleaning scraper 43 which removes whatever traces of the calcium magnesium chloride may be left after the belt passes the scraper 31. I also provide a cleaning brush I4 driven by a belt or chain 46 from the idler pulley also provide a drying mechanism for the belt comprising a plate 41 pivoted at 48 and having a rubber water removing portion 49 in contact with the belt as it passes over the end of the pulley. A tension spring serves to hold the rubber in contact with the belt. The rubber portion 49 running entirely across the belt removes the water with a so-called squeegee action.

In Fig.'4, I show'a modified. feeding arrangement in which a hopper 13| has an adjustable sliding gate 52 so arranged as to provide a slit or slot running transversally of the belt to discharge th'e calcium magnesium chloride in proper amounts. I also provide an adjustable spreader 53 for smoothing out the applied material. A similar leveling mechanism can, of course, be employed in the main feed embodiment.l

I have found that, with equipment such as that disclosed, calcium magnesium chloride can be delivered to the cooled metal surface at about 350? F. and removed continuously from the belt as it passes around the pulley Il in a solidified condition. There is no limit except a practical one to the length of the steel belt employed and for this reason the portion of the belt broken away is to be considered of indefinite length.

I2. At the feeding end of the apparatus I than about 65 or 70 F. in temperature.

I have found that with a belt having a total length of feet a relatively large output can be obtained even though the water is not less For best results, the material delivered from the belt should not be more than about 85 F.

The material is either delivered to the conveyor indicated at 36, or to a bin or hopper preparatory to bagging. If it is delivered to the conveyor mechanism, it may also be packaged immediately and without further processing, or it may be ground finer. Since it is recovered in the form of chips or flakes, it is in very good condition for subsequent treatment by comminuting apparatus.

It is understood that I may, if desired, employ special cooling equipment.

liquid cooled, sprayed against the lower side of the belt, and the liquid then again returned to be passed again in contact with the coolingA coils of the refrigerating equipment. Inasmuch as the material handled sells at a relatively low price vand since it is not necessary under most conditions to reach a very low temperature, I find that adequate results are obtained if Water is used no cooler than that found in natural sources such as lakes, rivers, or underground 1. The herein described` apparatus for treat-- ing calcium magnesium chloride and similar hylgroscopic materials to solidify them which comprises a pair of pulleys, a relatively wide and For example, cool-l ing water or other liquid may be passed in con tact with expansion coils of an ice machine, the

long endless metal belt extending around said pulleys, means for driving said pulleys to continuously advance the belt, means for applying a layer of the material to be treated to the belt adjacent one of said pulleys, means for supplying a cooling liquid onto the surface of said belt below the position occupied by said material, and means for causing said cooling liquid to be discharged on to another portion of said belt whereby to pre-cool the same before the application of the material to such portion.

2. The herein described apparatus for treating calcium magnesium chloride and similar hyygroscopic materials to solidify them which comprises a pair of pulleys, a relatively wide and long endless metal belt extending around said pulleys, means for driving said pulleys to continuously advance the belt, means for applying a layer of the material to be treated to the belt adjacent one of said pulleys, means for supplying 'a cooling liquid onto the surface of said belt below the position occupied by said material, means for causing said cooling liquid to be discharged on to another portion of said belt whereby to pre-cool the same before the application of the material to such portion, and means for drying said belt after the application of said liquid thereto.

3. The herein described apparatus for treating calcium magnesium chloride and similar hygroscopic materials to solidify them which comprises a pair of pulleys disposed in a substantially horizontal plane, a relatively wide and long endless metal belt extending around said pulleys, means for driving said pulleys to continuously advance the belt, means for applying a layer of the material to be treated to the belt adjacent one of said pulleys, means for supplying a cooling liquid onto the surface of said belt below the position occupied by said material, means for causing said cooling liquid to be discharged onto another portion of said belt whereby to pre-cool the same before the application of the material to such portion, and means for drying said belt after the application of said liquid thereto.

PETER R. MARTIN. 

